The global tug of war between Disney, Comcast and 21st Century Fox just got a little more interesting after it emerged that activist investor TCI Fund Management has built up a 4% stake in Rupert Murdoch’s Hollywood studio, making it among 21st Century Fox’s six largest shareholders.

The investment firm, run by London-based Chris Hohn, has been quietly building up a $3B stake in 21st Century Fox. At the end of 2017, it owned 0.7% of Fox’s class A shares and a small amount of Class B shares, but according to the Wall Street Journal, it has been adding to this and is expected to disclose its holdings next month.

The move is particularly interesting due to the multitude of global takeovers on the table in the U.S. and UK.

Disney is currently in the process of acquiring Fox’s entertainment assets in a $52.4B deal, while Fox is also attempting to buy the 61% of European pay-TV operator Sky that it does not own. The latter has been complicated after Comcast, yesterday, put forth an official $31B offer to buy Sky, forcing Sky’s directors to withdraw the recommendation of Fox’s deal after receiving the improved offer. Further to this, Comcast is eyeing another run at Fox after Murdoch rejected initial overtures from the Brian Roberts-run conglomerate, which could get in the way of the Disney deal. TCI’s involvement could add pressure to these deals, while also handing Hohn’s firm a significant return on investment if Comcast was return to Fox with an improved offer.

Sky is set to be the center of the next step of proceedings as Fox, or Disney, must decide whether to make an improved offer for the satellite broadcaster. Comcast’s improved offer of £12.50 per share, compared to Fox’s original £10.75 per share offer, comes after Sky secured valuable English Premier League soccer rights earlier this year in a much-reduced deal.

Hargreaves Lansdown analyst George Salmon called this a “game-changer”. “Sky has proven the Premier League deals are well worth the outlay. The group looks on course to deliver operating profits of £1.5bn this year, double what it earned ten years ago,” he added.

Investment firm Macquarie echoed these remarks in a note. “The outcome for Sky is dependent upon any response by Disney now that Comcast have firmed their offer,” it wrote. “Tension between Disney and Comcast could lift the offer price at least 10%.”

The corporate tug-of-war is becoming as intriguing as the plot to any Hollywood movie that could have been made by these companies and it will be interesting to follow the next stage in the plot. Expect more developments soon.