Bloodborne is currently free for PS Plus subscribers on the PlayStation Store, so grab it while it lasts.
Sony is apparently giving away Bloodborne to all PS Plus owners as a stealth freebie bonus for October's free games offering. This marks the second time Bloodborne has been free on PS Plus, and is a great game to pick up before the PlayStation 5 drops. Since it's a first-party game we expect Bloodborne will be fully backward compatible on the next-gen PS5, possibly with new updated features/FPS boosts.
Also remember Bloodborne will be free as part of the new PlayStation Plus Collection for PS5 owners. All PS Plus subscribers who grab a PS5 will get access to a pool of 18 must-play PS4 games including Bloodborne, God of War, Uncharted 4, and many others.
The free PS Plus library expands with Vampyr and Need for Speed: Payback on October 6, so pick those up too when they drop.