UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K

Current Report

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

April 27, 2026

Date of Report (Date of earliest event reported)

Registrant’s telephone number, including area code: (646) 886-8892

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01. Entry into a Material Definitive Agreement.

On April 27, 2026 the registration statement on Form S-1 (File No. 333-293531) (the “Registration Statement”) relating to the initial public offering (the “IPO”) of Plutonian Acquisition Corp II (the “Company”) was declared effective by the U.S. Securities and Exchange Commission (the “SEC”).

On April 29, 2026, the Company consummated its IPO, which consisted of 10,000,000 units (the “Units”). Each Unit consists of one Class A ordinary share, $0.0001 par value (“Class A Ordinary Share”) and one right of the Company (each, a “Right”), with each Right entitling the holder to receive one-fourth (1/4) of one Class A Ordinary Share upon completion of an initial business combination. The Units were sold at an offering price of $10.00 per Unit, generating gross proceeds of $100,000,000.

In connection with the IPO, the Company entered into the following agreements, forms of which were previously filed as exhibits to the Company’s Registration Statements, filed with the t SEC:

As of April 29, 2026, a total of $100,500,000 of the net proceeds from the IPO and the Private Placement (as defined below),  was deposited in a trust account established for the benefit of the Company’s public shareholders.

Item 3.02. Unregistered Sales of Equity Securities.

Simultaneously with the closing of the IPO, the Company consummated a private placement (the “Private Placement”) of an aggregate of 210,000 units (the “Private Units”) to the Sponsor at a price of $10.00 per Private Unit, generating total proceeds of $2,100,000. Each Private Unit consists of one Class A Ordinary Share and Right, with each Right entitling the holder thereof to receive one-fourth (1/4) one Class A Ordinary Share upon consummation of an initial business combination.

The Private Units are identical to the Units sold in the IPO except with respect to certain registration rights and transfer restrictions, as described in the Registration Statement. Additionally, such holders agreed not to transfer, assign or sell any of the Private Units or underlying securities (except in limited circumstances, as described in the Registration Statement) until 30 days after the completion of the Company’s initial business combination. The holders were granted certain demand and piggyback registration rights in connection with the purchase of the Private Units and the underlying securities.

The Private Units were issued pursuant to Section 4(a)(2) of the Securities Act, as the transaction did not involve a public offering.

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Effective as of April 27, 2026, the following individuals were appointed to the board of directors (the “Board”) of the Company: Arin Vahanian, Hao Shen and Joel A. Gallo. Additional information regarding, among other things, each individual’s background, board committee membership and compensatory arrangements is contained in the Registration Statement and is incorporated herein by reference.

On April 27, 2026, in connection with their appointments to the Board, each of the members of the Board entered into the Letter Agreement as well as an Indemnity Agreement with the Company filed, respectively, as Exhibits 10.1 and 10.7, herewith.

Other than the foregoing, none of the directors are party to any arrangement or understanding with any person pursuant to which they were appointed as directors, nor are they party to any transactions required to be disclosed under Item 404(a) of Regulation S-K involving the Company.

Item 5.03. Amendments to Certificate of Incorporation or Bylaws; Change in Fiscal Year.

On April 27, 2026, and in connection with the IPO, the Company adopted its Amended and Restated Memorandum and Articles of Association. The Amended and Restated Memorandum and Articles of Association is filed herewith as Exhibit 3.1 and is incorporated by reference herein.

Item 8.01. Other Events.

On April 27, 2026, the Company issued a press release announcing the pricing of the IPO, a copy of which is attached as Exhibit 99.1 to this Current Report on Form 8-K.

On April 29, 2026, the Company issued a press release announcing the closing of the IPO, a copy of which is attached as Exhibit 99.2 to this Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.